As someone who used Android prior to the iPhone 6, I suspect you're just running into a bit of culture shock. Android tries flexible; it tries to fit into your existing ways of using your other devices. With any iDevice, this is very deliberately not the case. It's in all cases Apple's way or the highway. If your issue is (as I imagine) that you have an existing, non-iTunes media library and you want to be able to make your device fit into your existing ways of working, I can tell you that there's no good way to do it. Support for that will always be second-class. If you want a pleasant and reliable user experience, you must convert your entire library to the file formats Apple support, and sync it through iTunes or through Apple's cloud services.
If anything justifies that lack of flexibility, it's the polish that Apple's absolutism affords: they have very few sets of assumptions about how the device is used, and make sure those few supported ways of using it work as well as they can. Apple does not try to offer everything to everyone. But once you do have everything in their ecosystem, it will all sync relatively painlessly, and if you buy new content from iTunes or iOS apps you won't need a computer at all. You get features like Continuity, and updates that aren't held up for months by manufacturers and carriers. Apps will support your device/screen size better, because there are only a handful of devices (rather than thousands) on the platform at any one time. When things do go wrong, you'll find that Apple has very good customer service. iOS, in short, may not always "just work", but it at least has a far better chance of "just working" than anything else on the market today. That is not despite but because Apple is so inflexible about how you may use your device.
Whether or not that's a good trade-off for you is something you have to consider very carefully before buying.
